(1) Field of the Invention
The present invention relates to a parking lock device for a saddle riding type vehicle, a so-called buggy, i.e., four-wheel vehicle for rough terrain which is maneuvered by a rider straddling the saddle type seat thereof by gripping its handlebars, and in particular relates to a parking lock device for locking the wheels of the vehicle so that it will not be moved when parked.
(2) Description of the Prior Art
There is a saddle riding type vehicle in which parking cams are provided in its drum brakes in the left and right rear-wheels so that by actuating the drum brakes the rear-wheels will not move when it is parked.
There is another configuration of a parking lock brake in which a lock gear is fixed on the gear shaft of the gear transmission connected to the engine while a parking actuator is provided on one side of the transmission cam drum for making a change in gear, so that the distal end of the actuator will mesh the lock gear to lock the gear shaft of the transmission to thereby lock the wheel shaft on the rear side of the gear transmission (see Japanese Patent Application Laid-Open Hei 11 No.3039911, for example).
In the configuration with parking cams provided in the drum brakes in the rear-wheels, if the drum brakes are replaced by disk brakes, the type of parking cams is quite different from that of the former and the braking effectiveness is lower, so that the design flexibility of the braking system becomes limited, resulting in inconvenience.
The configuration disclosed in Japanese Patent Application Laid-Open Hei 11 No.303991 has many drawbacks such as being heavier and costing more since it needs to have a cam for controlling the parking actuator on one side of the transmission cam drum and hence a longer transmission cam drum and a longer gear shaft, so needing many modified parts from those of the conventional make plus a wider transmission casing.
It is therefore an object of the present invention to provide a parking lock device for a saddle riding type vehicle, which can be arranged on the power output shaft of the gear transmission, is compact and needs fewer modified parts without the necessity of enlarging the transmission casing.
In order to achieve the above object, the parking lock device for a saddle riding type vehicle of this invention is configured as follows:
In accordance with the first aspect of the present invention, a parking lock device for a saddle riding type vehicle, for use in the driving force transmission system wherein the, engine power is transmitted as it is being varied in speed from the power output shaft of the gear transmission mechanism to the axle shafts via the intermediate shaft, includes: a lock gear arranged on the same shaft as the power output shaft; and a pivot element, cantilevered so as to sway about a pivot axle parallel to the power output shaft and having an engagement projection engageable with the lock gear and a slider abutment on the opposite side, and is characterized in that the engagement projection of the pivot element is adapted to engage the lock gear.
In accordance with the second aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above first feature is characterized in that the lock gear is arranged on the side opposite to the power output shaft with a gear therebetween.
In accordance with the third aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above first feature, for use in the driving force transmission system wherein the engine power is transmitted as it is being varied in speed from the power output shaft of the gear transmission mechanism to the front and rear wheel shafts via the intermediate shaft, includes: a lock gear arranged on the same shaft as the power output shaft;
a pivot element, cantilevered so as to sway about a pivot axle parallel to the power output shaft and having an engagement projection engageable with the lock gear on one side of the range of the swaying movement and a slider abutment on the opposite side; and an actuator made up of a rod and slider element which are able to advance and retract along the inner wall of the transmission casing and disposed on the side opposite to the lock gear with the pivot element arranged in between, the advancing and retracting direction of movement of the actuator being approximately parallel to the swaying direction of the pivot element, and is characterized in that the movement of the slider element causes the pivot element to sway so as to bring the engagement projection into mesh with lock gear.
In accordance with the fourth aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above third feature is characterized in that the actuator is comprised of a rod, an arm for causing the rod to advance and retract, a slider element which is movable relative to the rod, an urging element for urging the slider element toward the distal end of the rod and a stopper disposed at the distal end of the rod for constraining the movement of the slider element.
In accordance with the fifth aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above fourth feature, further includes: a constraint element positioned partway within the movable range of the slider element and fixed to the transmission casing wall and is characterized in that the constraint element constraining the advancing and retracting movement of the slider element by abutment against the tapered surface at the distal end of the slider element and causing the actuator to sway in the direction approximately perpendicular to the advancing and retracting direction of the slider element when the rod is moved further than a predetermined distance and swaying of the actuator releases the constraint on the advancing and retracting movement of the slider element and the slider element comes into sliding contact with the slider abutment of the pivot element so as to sway the pivot element.
In accordance with the sixth aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above third feature is characterized in that the pivot element is provided with a release urging element for urging the pivot element in the direction such that the pivot element will come away from the lock gear while the urging element for the slider element provides an elastic force which can urge the projection of the pivot element in the direction such that the projection will come into mesh with the lock gear.
In accordance with the seventh aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above fourth feature is characterized in that the pivot element is provided with a release urging element for urging the pivot element in the direction such that the pivot element will come away from the lock gear while the urging element for the slider element provides an elastic force which can urge the projection of the pivot element in the direction such that the projection will come into mesh with the lock gear.
In accordance with the eighth aspect of the present invention, the parking lock device for a saddle riding type vehicle having the above fifth feature is characterized in that the pivot element is provided with a release urging element for urging the pivot element in the direction such that the pivot element will come away from the lock gear while the urging element for the slider element provides an elastic force which can urge the projection of the pivot element in the direction such that the projection will come into mesh with the lock gear.
According to the present invention, since the engagement projection of the pivot element is adapted to mesh the lock gear provided on the power output shaft of the gear transmission so as to restrain and lock the power output shaft, it is possible to achieve the function of a parking lock device for preventing the vehicle from moving. Further, since the actuator is arranged on the side opposite to the lock gear with respect to the pivot element so that the pivot element will come into mesh with the lock gear by moving the actuator back and forth, it is possible to provide the pivot element in the form of a cantilever. This configuration contributes to making the parking lock device compact. Further, since the movement of the actuator is set to be approximately perpendicular to the swaying direction of the pivot element, this arrangement makes the layout space of the actuator compact.
According to the present invention, since the slider element is configured so as to be movable relative to the rod and since the advancing and retracting movement of the rod is transmitted to the slider element by the urging element, it is possible to provide a waiting structure with a simple configuration.
Illustratively, even if engagement projection of the pivot element has not yet engaged with the lock gear, a small amount of turn of the lock gear is able to cause the slider element being urged by the urging element to move and sway the pivot element so as to positively make the engagement projection fit into the indentation between teeth of the lock gear.
According to the present invention, as the actuator advances or retracts, the slider element sways in the direction approximately perpendicular to the movement by the function of constraint element so as to cause the engagement projection to mesh the lock gear. Therefore, the urging force along the advancing and retracting direction can be efficiently converted into that along the swaying direction.
According to the present invention, if engagement projection of the pivot element and the lock gear are not properly in mesh, it is possible to positively make the engagement projection mesh the lock gear when the lock gear turns a small amount.